docs: def unblock_ip(ip_address, pipe=None):
      """ unblock the given IP """
      do_commit = False
      if not pipe:
          pipe = REDIS_SERVER.pipeline()
          do_commit = True
      if ip_address:
          pipe.delete(get_ip_attempt_cache_key(ip_address))
          pipe.delete(get_ip_blocked_cache_key(ip_address))
          if do_commit:
              pipe.execute()